The purpose of this application is to apply event-related brain potential (ERP) measures as possible neuroelectric markers that reflect individual differences for susceptibility to alcohol abuse. This goal will be pursued by assaying well-defined groups of Mexican American individuals at Iow (LR) and high-risk (HR) for alcoholism, with equal and large numbers of female and male subjects employed for all comparisons. The effects of placebo beverage will be compared with an ethanol challenge condition before and after consumption using ERP paradigms evaluated during the Pl?s previous Alcohol Research Center grant period (1998-2002). Subjects in each group will be matched on relevant between-group factors to maximize neuroelectric differences. Preliminary data from Mexican American subjects suggest that the ERP profiles will differ between Mexican American LR and HR subjects in their response to ethanol intake. With sufficiently large and well-defined samples of female and male Mexican American LR and HR subjects, the complete results will provide insight on the utility of using ERP signatures as a possible endophenotype marker for alcoholism risk.